Typewriting machine



Aug. zo, 1940.

w. o. MlcHl-:LSEN

TYPEWRITING MACHINE Filed Oct. l. 1938 Patented Aug. 20, 1940TYPEWRITING MACHINE William 0. Mickelson, Woodhaven, N. Y., as-

signer to Royal Typewriter Companyflnc., New York, N. Y., a' corporationof New York Application October 1,1938, Serial No. 232,888

14 Claims.

This invention relates to typewriting machines, and more particularly tokeys for such machines. Keys embodying the invention may, however, be

. applied to finger-operated members of other machines, such as addingmachines, computing machines, and the like.

It is desirable that such keys be neat in appearance, formed of easilymanufactured and readily assembled parts, and capable of giving longservice with comfort to the operator and without becoming loose orotherwise losing emciency. An object of the present invention is toprovide a key having these desirable characteristics.

Another object is to provide a key including a mounting part or key cupsecured to a key lever and a disk positioned to be engaged by theoperators fingers and being firmly connected to the cup in a manner toeliminate possibility Aof the disks becoming loose in service.

Another object is to provide a key including a key cup and a disk offirm transparent material held firmly in the cup by snap-fasteninginterlocking means.

Other objects will become apparent from a reading of the followingdescription, the appended claims, and the accompanying drawing, inwhich:

Figure 1 is a top plan view of a key embodying the invention in oneform;

Figure 2 is a vertical sectional view taken on the line 2-2 of Figure 1;

Figure 3 is a vertical sectional view taken on the line 3-3 of Figure 1;

Figure 4 is a horizontal sectional view taken on the line 4--4 of Figure2;

Figures 5, 6, '7, 8, and 9 are vertical sectional views similar toFigure 3 and each showing a different embodiment of the invention;

Figure 10 is a group view showing in separated relation the parts ofwhich the Figure 9 embodiment is composed; and y Figure 11 is aperspective view of a key cap ring.

Among the several constructional forms of the invention shown for thepurposes of illustration, Figures 1 to 4 inclusive show a portion onlyof a key lever A, which may be of the usual form and which serves tomount a key assembly generally designated B. The assembly includes abase cup C comprising a bottom I and an annular outer wall 2. A washer 3disposed within the cup is provided with a slot 4 registering with aslot 5 in the cup bottom I, the two slots receiving a key lever shank 6which is peened as at 1 to secure the key lever, the cup, and the washertogether. The washer may be formed with raised flanges 8 to serve apurpose to be described.

A disk 9 of cardboard or the like displaying a character or characters Ion its upper face is positioned in the cup and rests upon the flanges 8.A disk II of firm, substantially unyielding, transparent,shatter-resisting material is positioned in the cup and over thecharacter' disk 8, and is snugly embraced by the cup wall 2.

, In accordance with one feature of the invention, the cup outer wall 2which preferably is of metal is slightly springy and is formed at itstop edge with a circumferential ridge I2 which extends inwardly towardthe axis of the cup and is received by a circumferential recess I3formed in the peripheral surface of the disk II. The ridge I2 and recessI3 are correspondingly shaped so as to provide a snap-fasteningfrictional interlocking or interengaging connection directly between thecup and the transparent disk. In the form shown, 4the ridge I2 andrecess I3 are rounded in transverse section, making it possible tofo'rce the disk II downwardly into the cup in a manner to spring the cupwall 2 outwardly until the ridge I2 entersl the recess I3 forming thesnap fastening referred to above. To facilitate the introduction of thedisk II into the cup, the peripheral surface portion of the disk belowthe recess I3 may betapered as indicated at I4. The

resulting assembly is permanently tight and vneat in appearance, itbeing noted that the top edge of the cup wall substantially merges withthe marginal upper surface portion of the transparent disk.

In order that the disk II may be readily removed from the cup, thebottom of the cup preferably is provided with one or more apertures Iadapted to accommodate a tool projected inwardly from outside the cupandpushed against the bottom of the character disk 9 so as to force thelatterand the transparent disk I I out of the cup, this being possiblebecause of the springiness of the cup outer wall 2. The apertures I5extend straight through the cup bottom wall, the axes of the apertureslbeing substantially perpendicular to the cup bottom. Thus the tool mayproject through the cup bottom substantially perpendicular thereto andperpendicular to the disk 8 for applying ejecting pressure to the disks9 and II in a direction substantially parallel to the cup wall 2.

In order to assure a firm interlocking connection between the cup 2 andthe transparent disk II, it is desirable that the relative diam-v etersof,the circumferential ridge I2 and the recess I3 be such as to requirethe exertion of a considerable force to insert the disk into the cup.Consequently the disk must be capable of withstanding considerablepressure without shattering or chipping. The material best suited forforming the transparent disk for use in a construction .as described hasbeen found to be Lucite, a methyl methacrylate plastic. This material iscrystal-clear, is about half as heavy as common glass, is strong anddurable. and possesses marked resistance to chipping or .shattering. Itis. however, iirm, and a disk of the proportions shown in Figures 1 to 4when formed of this material,will be substantially unyielding ascompared to other materials such as rubber and some other moldedplastics. Properties of this material rendering it especially adaptedfor such use are further describedin the co-pending application ofBernard Joseph Dowd, Serial Number 232,863, nled October 1. 1938.

The relative separating movement between the peripheral surface of thedisk II and the cup wall 2 is edected mainly by outward springing of thecup wall, which, although preferably of metal and thus relatively hard,is capable of the necessary outwardmovement.

The key assembly B* shown in Figure 5 differs from the key 'assembly Bpreviously described in that, in the assembly B", the ridge I2-islocated intermediate the top and bottom limits of the wall 2* of thecup C, and the circumferential reoess Ill of the disk II is positionedaccordingly, so that, when the ridge andrecess are in interlockingrelation, the top of the wall 2* will substantially merge with themarginal upper surface of the disk II. The .disk II* also differs fromthe disk II of the assembly B in that it is not tapered corresponding tothe taper I 4 of the disk II in the assembly B. 'Ihe bottom I'L of thecup C* is the same as the bottom I of the cup C. The other parts of theassembly B are identical with corresponding parts in the assembly B, andare designated by referencechar-y acters the same as those designatingidentical parts in Figures 1 to 4.

The assembly Bb shown in Figure 6 differs from the assembly B shown inFigure 5 in that in the assembly Bb of the ridge I2 of the wall 2b ofthe cup Cb and the recess Il" of the transparent disk IIb are sorelatively positioned that the disk extends somewhat above the top edgeof the cup wall 2b. 'I'he assembly.Bb further comprises a key cap ring IC which fits over the cup wall 2h and is provided with an inwardlydirected flange I1 which preferably is tapered off in thickness so as tomerge substantially with the marginal upper surface of the transparentdisk Il". Ears Il formed integrally with the cap ring Il are turnedunder the bottom I of the cup. The other parts of the assembly Bh areidentical with corresponding parts of the assembly BI (Figure 5), andaccordingly are designated by reference characters the same as thoseapplied to the identical parts in the assembly B shown in Figure 5.

'I'he assembly B shown in Figure 7 is similar to the assembly B shown inFigures 1 to 4 with the exception that the transparent disk II'= havingthe circumferential recess II is convex on its lower face rather thanbeing flat as in the assembly B, and the character disk 0 accordingly iscurved to conform to the convexity of the bottom of the disk II. Otherparts identical with corresponding parts of the assembly B aredesignated by reference characters the same 8S those designating theidentical parts in Figures l to 4 inclusive.

The assembly B'l shown in Figure 8 differs from the assembly shown inFigures 1 to 4 in that the cup C comprises a bottom I4 and a side wall 2provided with a ridge I2*i which is"de formed inwardly, so that itsupper inner surface portion is inclined upwardly-inwardly toward theaxis of the cup. The recess Il*i in the periphery of the transparentdisk II is angular in transverse section, and has a circumferentialsurface Ild inclined to correspond with the inclination of the innersurface of the ridge |24. In this vform the transparent disk is providedwith a marginal portion 204 above the recess Il", and extending over andcovering the top of the cup wall 2. The bottom peripheral edge portionof the disk I Ii is tapered downwardly-inwardly as at I4d to facilitateinsertion of the transparent disk into the cup. Other parts of theassembly BI are identical with corresponding parts of the assembly B,and therefore are designated by reference characters the same as thosedesignating the identical parts in the assembly B shown in Figures 1 to4 inclusive. The assembly Bd shown in Figure 8 is such that the entirefinger-engageable portion of the assembly is comprised by thetransparent disk, which entirely covers the key cup.

In the assembly B shown in Figures 9 and 10, a cup C supported on a keylever A comprises a cup bottom I' and a plane annular outer wall 2having no ridge corresponding to the ridges described with reference tothe forms previously referred to. The cup C' and a washer I are joinedto the key lever A as at 4, l, C, and 'I in the same manner as describedwith reference to Figures l to 4, and a character disk 9 is supportedwithin the cup resting upon the flanges l of the washer I. A key capring 16 fits snugly over the cup and is provided with a flange I 1 whichextends into a circumferential recess I2 in the transparent disk II',thus retaining the parts in assembled relation with the cooperation ofears Il integral with the cap ring and extending under the cup bottom IThe showing in the drawing of the inward extent of the cup wall ribs orridges may be considered as somewhat exaggerated for clear illustration.'Ihe ribs or ridges are of such size or inward extent that the snapaction interlocking connection between the cup walls and disks can beeffected because of a slight springiness of the ribs or ridges and/orthe cup walls All of the assemblies disclosed are of neat appearance.are formed of easily manufactured and readily assembled parts,v and arecapable of giving long service with comfort to the operator withoutbecoming loose or otherwise losing efficiency. The embodiments of theinvention disclosed are preferred, but changes may be made in theconstruction and arrangement of the parts without departing from theinvention as defined in the claims.

I claim:

1. In a key of the character described. the combination of a base cuphaving an annular outer wall formed with means projecting inwardlytowards the axis of the cup, said inwardly projecting means beingslightly springy; and a -disk of firm shatter-resisting materialpositioned in the cup, the periphery of said disk being snugly embracedby said annular wall and being recessed to receive said inwardlyprojecting means.

2. In a key of the character described, the combination of a base cuphaving a hard annular outer wall formed with a circumferential ridgeprojecting inwardly towards the axis of the cup, said ridge beingslightly springy; and a disk of firm shatter-resisting materialpositioned in the cup, the periphery of said disk being snugly embracedby said annular wall and being circumferentlally recessed to receivesaid inwardly projecting ridge.

3. In a key of the character described and equipped to display acharacter, the combination of a base cup having a hard annular outerwall formed with a ridge projecting inwardly towards the axis of thecup, said ridge being slightly springy; and a disk of firm,substantially unyielding, shatter-resisting, transparent materialpositioned in the cup so as to cover the displayed character, theperiphery of said disk being embraced by said annular wall and having arecess which receives said ridge to lock the disk in the cup.

4. In a key of the character described, the combination of a base cuphaving an annular outer wall formed with a ridge projecting inwardlytowards the axis of the cup, said ridge being slightly springy; acharacter disk supported in the cup and a disk of iirm transparentmaterial positioned in the cup over the character disk, the periphery ofsaid transparent disk having a recess which receives said ridge to lockthe disk in the cup.

5. In a key of the character described, the

combination of a base cup having an annular outer walll formed with aridge projecting inwardly towards the axis of the cup', said ridge beingslightly springy; a character disk supported in the .cup and a disk ofiirm transparent material positioned in the cup over the character disk,the periphery of said transparent disk having a recess which receivessaid ridge to lock the disk in the cup, the bottom of said cup having anaperture adapted to accommodate a tool extended in from outside the cupto bear against the character disk for forcing the disk out of said cup.

6. In a key of the character described, the combination of a base cuphaving an outer wall; a disk of firm transparent material positioned inthe cup; and springy interengaging means on said wall and the peripheryof said disk providing a snap fastening between said cup and disk.

7. In a key of the character described, the combination of a base cuphaving an outer wall; a disk of firm transparent material positioned inthe cup; and springy interengaging means on said Wall and the peripheryof said disk providing a snap fastening between said cup and disk, thebottom of said cup having an aperture adapted to accommodate a toolextended in from outside the cup to forcibly eject said disk from saidcup.

8. In a key of the character described, the combination of a base cuphaving a bottom and a wall substantially perpendicular to the bottom:and a disk positioned in said cup and normally retained therein by saidWall, the bottom of said cup being provided with an aperture adapted toaccommodate a tool extended in from outside the cup to forcibly ejectthe disk from the cup, said aperture extending straight through the cupbottom with its axis substantially perpendicular thereto, whereby thetool may project through the cup bottom substariisally perpendicular tosaid bottom and said k for applying diskejecting pressure in adirection' substantially parallel to said cup wall.

9. In a key of the character described, the combination of a metallicbase cup having an outer annular wall; a disk of firm, transparent,nonshatterable molded plastic material ,positioned in the cup; and snapaction interengaging means integral respectively with said cup wall andthe periphery of said disk providing a direct frictional interlockbetween said cup and disk.

10. .In a key of the character described, thecombination of a base cuphaving an annular outer wall formed along its upper edge with an annularrib extending inwardly toward the axis of the cup; and a disk of firm,shatter-resisting material positioned in the cup and being embraced bysaid' cup outer wall, the upper peripheral edge portion of said diskbeing formed with a circumferential recess receiving said annular riband cooperating therewith to provide a direct snap fastening betweensaid cup and disk, said rib and recess being correspondingly shaped intransverse section and said rib being springy whereby said disk may beforced into and out of its fastened position in said cup.

11. In a key of the character described, the combination of a base cuphaving an annular outer wall formed intermediate its top and bottomlimits with an annular rib extending inwardly toward the axis of thecup; and a disk of iirm, shatter-resisting material positioned in thecup and being embraced by said cup outer wall, the peripheral edge ofsaid disk being formed gwith a circumferential recess receiving saidannular rib and cooperating therewith to provide a direct snap fasteningbetween said cup and disk, said rib and recess being correspondinglyshaped in transverse section and said rib being springy whereby saiddisk may be forced into and out of its fastened position in said cup,the

top of said cup outer wall and the contiguous top surface portion ofsaid disk being substantially ush with each other.

12. In a key of the character described, the combination of a base cuphaving an annular outer wall formed with an annular rib extendinginwardly toward the axis of the cup; a disk of firm, shatter-resistingmaterial positioned in the cup and being embraced by said cup outerwall, the peripheral edge of said disk being formed with acircumferential recess receiving said annular rib and cooperatingtherewith to provide a direct snap fastening between said cup and disk,said rib and recess being correspondingly shaped in transverse sectionand said rib being springy whereby said disk may be forced into and outof its fastened position in said cup; and a cap ring snugly embracingsaid cup wall and having a flange extending inwardly over the top edgeof said wall, the top surface of the fiange being substantially iiushwith the marginal top surface of the disk.

13. In a key of the' character described, the

clined portion of the cup wall to provide a di- 75 rect snap fasteningbetween the cup and disk, the disk having a marginal portion above saidrecess extending over the top of the cup wall and having adownwardly-inwardly bevelled periph- -eral bottom edge.

14. In a key of the character described, the combination of a base cuphaving an annular outerwall: a disk oi iirm, shatter-resisting materialpositioned in the (sup,- the upper peripheral 10 edge portion of saiddisk extending above the top of the cup wail and being formed with acircumferentiai recess; and a key cap ring fitting the outside of saidcup wall snugly and having at its top an inturned flange received bysaid recess and providing therewith a snap fastening between said diskand ring, the top of said ring being substantially iiush with themarginal top portion of said disk.

